Chlorofluorocarbons (CFCs, i.e., compounds containing only carbon, fluorine and chlorine) have been used for many years as refrigerants, heat transfer media, foam expansion agents, aerosol propellants, solvents, fire extinguishants and power cycle working fluids. For example, various CFC solvents have been used as cleaning liquids for the removal of contaminants from contaminated articles and materials. Certain fluorine-containing organic compounds such as 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) have been reported as useful for this purpose, particularly with regard to cleaning organic polymers and plastics which may be sensitive to other more common and more powerful solvents such as trichloroethylene or perchloroethylene. Recently, however, there have been efforts to reduce the use of certain compounds such as trichlorotrifluoroethane which also contain chlorine because of a concern over their potential to deplete ozone. Consequently, there is a worldwide effort to find alternative compounds.
The properties of halogenated hydrocarbons can be influenced by the arrangement of the halogens (and hydrogen, when present) on the carbon framework. One of the challenges in preparing compounds containing fluorine and hydrogen has been to achieve the desired arrangement of such substituents. When more than one hydrogen is present in the molecule, one arrangement involves providing a hydrogen on different carbons spaced a selected distance from one another along a carbon chain. For example, in a compound of the formula C.sub.4 H.sub.2 F.sub.8, it can be desirable to provide a hydrogen substituent on each of two carbon atoms which are separated from one another by a chain of two other carbon atoms. 1,1,2,2,3,3,4,4-Octafluorobutane (i.e., CHF.sub.2 CF.sub.2 CF.sub.2 CHF.sub.2 or HFC-338pcc) is such a compound. HFC-338pcc forms useful blends, and particularly azeotropes, with solvents such as alcohols, ketones, and other halogenated solvents to form compositions useful for cleaning surfaces, especially electronic components as disclosed in U.S. Pat. Nos. 5,250,208, 5,221,493 and 5,194,170. There is a need for non-chlorinated solvents like HFC-338pcc (which have little effect on the ozone layer) as replacements for more chlorinated solvents such as CFC-113.